Negotiator, did you change with a new CDI or old one???, as i think this cdi may have an endemic problem??
So if this helps anyone a standard dt125 cdi (one less lead no red and black wire) does not seem to work on a straight swap,,, although all other colours match. Thats a bit strange as the red and black only gives the ignition off signal from what I can gather on an ohm test. With the oem cdi though if you disconnect this red and black cable (which is missing from a standard dt cdi) the bike will give no spark. The red and black wire seems to be open circuit for the ignition,,, but in open position of ignition cdi will not spark... At this stage I am thinking the irregular good run bad run no run runs great is probably cdi sporadic... One guy on youtube hits the cdi then it runs bad or runs good,,, this could be internal solder points,,, so am thinking that may be it at this stage, and will test this accordingly..
he swaps out to a 2rh-mo and changes the leads